Electric-lamp holder



(No Model.)

1:". SOHAEFER.

ELECTRIC LAMP HOLDER.

No. 339, 217. Patented Apr. 6, 1886.

1 fl :w aw D v r. fi m 9 5 E 5 E N, PEI'ERs Phctuumognphcr. wnmn m D. c;

UNTTED STATES PATENT Orricn.

FREDERICK SOHAEFER, OF BOSTON, lllASSAOHUSETTS.

ELECTRIC-LAMP HOLDER.

SPECIFICATION forming part of Letters Patent No. 339,217,6iatedApi-i1 6,1 886.

(No model.)

[0 aZZ whom it may concern.-

Be it known that I, FREDERICK SCHAEFER, of Boston, county of Suffolk,State of Massachusetts, have invented an Improvement in Electric-LampHolders, of which the following description, in connection with theaccompanying drawings, is a specification, like letters on the drawingsrepresenting like parts.

Myinvention has for its object the improvement of incandescent-lampholders,whereby a sure and reliable contact is made between the terminalelectrodes of the carbon filament and the contact-pieces secured to theusual insulating-block.

My invention also has for its object the simplification of theconstruction of incandescent-lamp holders, wherebya damaged lamp may bequickly replaced without necessitating the removal of the holder fromits fixture or support.

Myinvention consists of a lamp-holder constructed and arrangedsubstantially as here inafter particularly set forth and claimed.

Figure l is a sectional elevation of a lamp and holder embodying myinvention. Fig. 2 is a plan view of the holder with the lamp removed,and Fig. 3 a detail to be referred to.

The sleeve or case D may be struck up from sheet metal and shaped asshown, and is provided at one end with a screw-threaded socket, k, bywhich the holder may be secured to any suitable or proper support in anydesired place. Vithin the sleeve or case I have placed a spring, on, andalso an insulating-block, a provided with independent contact-pieces c0, (see Fig. 2,) the latter having a central opening, through whichconducting-wires areled, to be fastened to the contact-pieces by headedscrews s, as shown in Fig. 2, the said spring at (shown as entering arecess in the said block) normally forcing the contact-pieces c 0 upagainst the terminal electrodes ff of the carbon filaments a a, the saidterminal electrodes being herein shown as lugs projecting from theplaster-ofparis or other equivalent mold, Z), they being connected tothe said filaments a a by the usual platinum wires, a a", the said lugsand contact-pieces establishing good electrical con nection between thelamp B and the holder 0.

The vertical movement of the insulatingbloek a within the sleeve or caseis limited by suitable stops, herein shown as screws (1, connected withthe said block, they being extended through slots (1 in the said sleeveor case and striking against the ends of the said slots; but it isevident other means may be employed to limit the said movement, such asa shoulder projecting from the inside of the case D, or a re-entrantportion of the case itself above the said block, as shown at the left ofFig. l in dotted lines.

To secure the lamp B to the holder 0, I have surrounded theplaster-of-paris mold b by a band, (I, provided with projections c c,which,

entering slots at a in the case D, (see Fig. 2,)

are thereafter by a partial rotation of the lamp caused to enter andtravel in an annular groove, 6, (see Fig. 3,) and form with the groovein the said sleeve or case at the ends of the vertical slots abayonet-joint to connect the lamp with the sleeve or case D, the lampbeing stopped in its rotary movement as soon as the lugsff strike theheaded screws 3', (shown in Fig. 3,) the position of the lugs beingshown in Fig. 2 in heavy dotted lines.

During the movements described of thelamp the terminal electrodes actagainst the contactpieces 0 c and push the insulating block back againstthe action of the springm, which supports it in a yielding manner, andas the lamp is rotated the terminal electrodes bear against or wipe overthe contactpieces, thus forming a rubbing contact and securing the bestpossible electrical connection.

Contact pieces shaped substantially as shown in Fig. 2, in operation,may be made to constitute a switch,whcreby the operator, by turning thelamp so that the terminal electrodes will occupy a position between thesaid contact-pieces c c. as indicated by the light dotted lines f f inFig. 2, can cut the said lamp out of circuit, and that without removingit from the said sleeve or case.

Inasmuch as the lamp and holder are separate and detachable, it isevident that the said lamp, if broken or otherwise damaged, can bequickly removed and replaced by another without disturbing the holder,the construction of which is so simple that it will require very littlerepairing.

I am aware that a spring has been used in connection with a lamp and itsholder; but as heretofore employed the spring has performed an entirelydifferent purpose or function from that in the combination in which itis herein placed; andIam aware, also, that alarnp and its holder havebeen attached by a bayonetlike-joint connection.

I claim- 1. In an incandescentlamp, a sleeve or case having stops tocontrol the extent of outward movement of aninclosed insulating-block,and provided with a socket, combined with the insulatingblock havingcontact-pieces, and with a spring supported in the bottom of the sleeveor case, and acting at one end upon the under side of and moving thesaid insulatingblock outward, substantially as described.

2. The lamp provided at its neck with terminal electrodes/ and havingprojections c 0, combined with a sleeve or case having a groove, 6,slotted at n n, to enable the said projections to enter the said groove,and having stops and a socket connected with the said sleeve or case, aspring located in the said sleeve or case and supported by it at or nearthe said socket, and the insulating-block provided with contactpieces,whereby when the projections on the neck of the lamp are entered intoand made to followin the groove 6 the terminal electrodes act againstthe 0011- tact-pieees e c and force the insulating-block back into thesleeve or case, compressing the said spring, the terminal electrodesrubbing or sliding over the contact-pieces as the lamp is being turnedto secure it in place, substantially as described.

In testimony whereof Ihave signed my name to this specification in thepresence of two subscribing witnesses.

FREDERIOK SGHAEFER.

Witnesses:

J. H. CHURCHILL, B. J. NoYEs.

